This invention relates to corrosion inhibition. More particularly, this invention relates to novel plastic articles which provide volatile corrosion inhibition.
Volatile or vapor phase corrosion inhibitors have been used in a variety of applications where visible coatings such as oil or grease or other permanent coatings such as paints are unacceptable for various reasons. Sodium nitrite, amine nitrite salts, organic amines, carboxylic acids and organic amine carboxylic acid salts have all been disclosed singularly and in combination in volatile corrosion inhibiting compositions (e.g. as described in U.S. Pat. Nos. 2,629,649: 2,711,360: 2,986,447: 3,398,095: 3,433,577: 3,785,975: and 3,967,926). Sheet materials useful for packaging metal parts containing volatile corrosion inhibiting compositions have also been disclosed (e.g. as described in U.S. Pat. Nos. 2,717,843: 2,739,871: 2,829,080: and 3,080,211). Sodium nitrite is known as an effective volatile corrosion inhibitor when carbon dioxide and water are present in the air. However, in the absence of carbon dioxide, its effectiveness as a volatile corrosion inhibitor drops off abruptly, as described in Metaux 1972 47(558), 41-50.